
x1, y1, x2, y2 = (float(i) for i in input().split())
x_range = x2 - x1
y_range = y2 - y1

distance = pow(pow(x_range, 2) + pow(y_range, 2), 1/2)

print(distance) float(i) for i in input().split() for i in input().split() i input().split() ().split () input split for i in input().split() float(i) float i x1, y1, x2, y2 = (float(i) for i in input().split()) x1 (float(i) for i in input().split()) y1 x2 y2 x_range = x2 - x1 x_range x2 - x1 x2 x1 y_range = y2 - y1 y_range y2 - y1 y2 y1 distance = pow(pow(x_range, 2) + pow(y_range, 2), 1/2) distance pow(pow(x_range, 2) + pow(y_range, 2), 1/2) pow pow(x_range, 2) + pow(y_range, 2) pow(x_range, 2) pow x_range 2 pow(y_range, 2) pow y_range 2 1/2 1 2 print(distance) print distance y1, x2, y2 = (float(i) for i in input().split()) (float(i) for i in input().split()) y1 x1, y1, x2, y2 = (float(i) for i in input().split()) (float(i) for i in input().split()) x1 y_range = y2 - y1 y2 - y1 y_range x_range = x2 - x1 x2 - x1 x_range x2, y2 = (float(i) for i in input().split()) (float(i) for i in input().split()) x2 y2 = (float(i) for i in input().split()) (float(i) for i in input().split()) y2 distance = pow(pow(x_range, 2) + pow(y_range, 2), 1/2) pow(pow(x_range, 2) + pow(y_range, 2), 1/2) distance

x1, y1, x2, y2 = (float(i) for i in input().split())
x_range = x2 - x1
y_range = y2 - y1

distance = pow(pow(x_range, 2) + pow(y_range, 2), 1/2)

print(distance)